Hi all, I would PLEASE like some help with ordering my network. Modem/router, router, switches and weird devices

I will try to be as clear and detailed in what i wanting to acheive, i have some knowledge but when multiple routers, switches and devices are needed to be setup i could end up digging myself a hole. I will likely tell you some useless info but wanted correspondence with as little questions back as possible.

I have a Dlink 2740b Modem router which only server one PC, wired and sometimes wireless, from the dlink runs an ethernet line through into the adjoining building. In this building i have a Belkin F6D4230-4 v1 "enhanced wireless router" and would would it to put out its own separate SSID and DHCP delegation (there is no problem if the from the Dlink network access is able to whole network and vice versa if this matters). Under the Belkin SSID i would like to connect the following devices - 2 macs (Mac mini, macbook pro) other devices wanted to be wired to this network include a NAS, 3 ip cameras, xbox360, and a spare port or 2 somewhere would be good for customers.

Now from this network (belkin) i have ethernet running into a separate building where i would like to operate 2 network cameras, TV, xboxone, Macmini, MacPro, and again have a couple of spare ports for internet users. This Building it way too far to receive Wireless and i am not concerned or looking to extend it that far.

Basically from anywhere in the Belkin network i would like to be a ables to access all network cameras on any of the mac devices locally. Relocation of the NAS can be done if needed.

What i am not sure of is where and what the switches/router need to be plugged into to make them talk as to allow the above access. Things like file sharing between each MAC via LAN is also necessary.

To allow enough ports i have some switches, these include a Dlink 5 port, Netgear 5 port and an 8 port switch, again of the gigabit variety.

Again, from that first now active ethernet line coming out of the DLINK modem and sitting next to my Belkin and switches, what to plug where, and orders etc.

I am somewhat familiar with configuring a single modem on our telstra ADSL DLINK and port forwarding etc. and also all the network cameras, ordering of wires is basically all i need as my knowledge of switches a limited...

I hope i have been specific enough, if any questions have been left out i can promptly reply, forgive my basic knowledge and want for free advice, haha, thanks

i have a diagram i can e-mail thanks